1. Technical Field
Example embodiments of the inventive concept relate in general to technology of generating a tactile signal using an audio signal, and more specifically, to method and an apparatus for generating haptic signals using a part to be noted in the characteristics such as a frequency and an intensity of an audio signal.
2. Related Art
A haptic stimulus that capable of sensing when a finger of a man touches an object has a tactile feedback and a kinesthetic. The tactile feedback is sensed when an object is touched to a surface of a skin and the kinesthetic force feedback is sensed when movements of a joint and a muscle are obstructed.
These haptic feedbacks are mostly and firstly used in a medical field. Due to characteristics of the medical field, particularly, an invasive surgery field, since it is difficult to endure a training process through trial and error and a high cost is required, the haptic feedbacks which are a relatively economical tool have been used.
For example, a three-dimensional image capable of directly operating an affected area of a virtual patient while watching a three-dimensional anatomical structure displayed on a computer screen is displayed on the computer screen in real time. And also, a tactile which is likely to touch an actual skin tissue using a mechanical receptor such as a small pin which is movable by compressed air or electricity, etc. is transferred, and an environment which is almost similar to an actual situation is implemented.
This haptic stimulus is differently recognized according to a speed and a force rubbing an object, and a physical property of the object. Accordingly, if the same man desires to recognize different haptic stimuli, the physical property of the object should be changed. For this, proposed is technology of providing various haptic stimuli to a user by forming a plurality of fine protrusions on a contact surface on which a hand is touched, changing the lengths of the plurality of fine protrusions and intervals between the plurality of fine protrusions, and adjusting a displacement and a frequency of vibrations of the fine protrusions.
Meanwhile, there has been a trial for playing a sound three-dimensionally by combining the haptic stimuli also in an audio field. It is used that terminology referred to as a fourth dimension evolved from a third dimension, and this is a marketing terminology unlike second dimension and the third dimension. When transferring the sound, for example, it may be understood that a tactile signal involved in the sound is included in the fourth dimension in this specification.
Recently, the haptic technology has been attracting attention as a method of transmitting information to various multimedia contents such as a game, a movie, a music, etc. using a tactile, and products such as a vibration earphone and a headphone, a home theater system, a four dimensional theater, a tangible game console, a smart phone and a tablet PC have been released. These products are increasing immersion and satisfaction of the user as a multisensory display device using not only visual and auditory senses but also a tactile sense in user experience of the multimedia contents.
In order to transfer touch information, currently, a method in which the man directly makes a signal through an operation such as a composition or which uses as a vibration signal by filtering a low frequency component of an audio signal is mostly used. However, the method in which the man directly makes the tactile signal has a disadvantage in which many time and a high cost are required, and the method which uses the low frequency component of the audio signal naturally does not naturally harmonize with the audio signal compared with the method in which the man directly makes the tactile signal. Studies on a method of genefating the tactile signal which is naturally harmonized with the audio signal without consuming many time and the high cost are required.